#!/bin/sh

# Copyright (C) 2018-2022 Internet Systems Consortium, Inc. ("ISC")
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

# Check hashes
#
# This developer script verifies recorded hashes still match the
# result of SHA-256 checksums of the YIN format.
# Requires yanglint to translate YANG to YIN formats and openssl
# for a system independent SHA-256.

# Exit with error if commands exit with non-zero and if undefined variables are
# used.
set -eu

# Change directory to the YANG modules' directory.
cd "@abs_top_srcdir@/src/share/yang/modules"

amend=false
if test "${1-}" = '-a' || test "${1-}" = '--amend'; then
    amend=true
fi

exit_code=0

LIBYANG_PREFIX='@LIBYANG_PREFIX@'

# Find yanglint.
if test -f "${LIBYANG_PREFIX}/bin/yanglint"; then
    yanglint="${LIBYANG_PREFIX}/bin/yanglint"
    LD_LIBRARY_PATH="${LD_LIBRARY_PATH-}:${LIBYANG_PREFIX}/lib:${LIBYANG_PREFIX}/lib64"
    export LD_LIBRARY_PATH
elif command -v yanglint; then
    yanglint='yanglint'
else
    exit_code=$((exit_code | 2))
    printf 'ERROR: cannot find yanglint.\n' >&2
    exit "${exit_code}"
fi

for m in *.yang; do
    hash1=$("${yanglint}" -f yin "${m}" | openssl dgst -sha256 | sed 's/(stdin)= //' | sed 's/SHA2-256//')
    h="hashes/$(basename "${m}" .yang).hash"
    if test -f "${h}"; then
        hash2=$(cat "${h}")
        if test "$hash1" != "$hash2"
        then
            exit_code=$((exit_code | 4))
            printf 'ERROR: hash mismatch on %s expected %s in %s\n' "${m}" "${hash1}" "${h}" >&2
            if "${amend}"; then
                printf '%s\n' "${hash1}" > "${h}"
            fi
        fi
    else
        exit_code=$((exit_code | 8))
        printf 'ERROR: missing hash file %s for %s\n' "${h}" "${m}" >&2
        if "${amend}"; then
            printf '%s\n' "${hash1}" > "${h}"
        fi
    fi
done

exit "${exit_code}"
